MultipartPostHandler.py

Go to the documentation of this file.

# From http://peerit.blogspot.com/2007/07/multipartposthandler-doesnt-work-for.html
 
 
"""
Usage:
  Enables the use of multipart/form-data for posting forms
 
Inspirations:
  Upload files in python:
    http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/146306
  urllib2_file:
    Fabien Seisen: <fabien@seisen.org>
 
Example:
  import MultipartPostHandler, urllib2, cookielib
 
  cookies = cookielib.CookieJar()
  opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookies),
                                MultipartPostHandler.MultipartPostHandler)
  params = { "username" : "bob", "password" : "riviera",
             "file" : open("filename", "rb") }
  opener.open("http://wwww.bobsite.com/upload/", params)
 
Further Example:
  The main function of this file is a sample which downloads a page and
  then uploads it to the W3C validator.
"""
from __future__ import print_function
 
from builtins import object
from email.generator import _make_boundary
import mimetypes
import os, stat
import sys
from io import StringIO
 
IS_PY2 = sys.version_info[0] == 2
 
if IS_PY2:
    from urllib2 import BaseHandler, build_opener, HTTPHandler
else:
    from urllib.request import BaseHandler, build_opener, HTTPHandler
 
if IS_PY2:
    import urllib as ulib
else:
    import urllib.parse as ulib
 
 
class Callable(object):
    def __init__(self, anycallable):
        self.__call__ = anycallable
 
# Controls how sequences are uncoded. If true, elements may be given multiple values by
#  assigning a sequence.
doseq = 1
 
class MultipartPostHandler(BaseHandler):
    handler_order = HTTPHandler.handler_order - 10 # needs to run first
 
    def http_request(self, request):
        data = request.data
        if data is not None and type(data) != str:
            v_files = []
            v_vars = []
            try:
                 for(key, value) in list(data.items()):
                     # 'file' type doesn't exist in python3 and we didn't use it. Removed if:
                     v_vars.append((key, value))
            except TypeError:
                systype, value, traceback = sys.exc_info()
                raise TypeError("not a valid non-string sequence or mapping object", traceback)
 
            if len(v_files) == 0:
                data = ulib.urlencode(v_vars, doseq)
            else:
                boundary, data = self.multipart_encode(v_vars, v_files)
 
                contenttype = 'multipart/form-data; boundary=%s' % boundary
                if(request.has_header('Content-Type')
                   and request.get_header('Content-Type').find('multipart/form-data') != 0):
                    print("Replacing %s with %s" % (request.get_header('content-type'), 'multipart/form-data'))
                request.add_unredirected_header('Content-Type', contenttype)
 
            request.data = bytearray(data, 'latin1')
 
        return request
 
    def multipart_encode(self, these_vars, files, boundary = None, buf = None):
        if boundary is None:
            boundary = _make_boundary(os.getuid + os.getpid())
        if buf is None:
            buf = StringIO()
        for(key, value) in these_vars:
            buf.write('--%s\r\n' % boundary)
            buf.write('Content-Disposition: form-data; name="%s"' % key)
            buf.write('\r\n\r\n' + value + '\r\n')
        for(key, fd) in files:
            file_size = os.fstat(fd.fileno())[stat.ST_SIZE]
            filename = fd.name.split('/')[-1]
            contenttype = mimetypes.guess_type(filename)[0] or 'application/octet-stream'
            buf.write('--%s\r\n' % boundary)
            buf.write('Content-Disposition: form-data; name="%s"; filename="%s"\r\n' % (key, filename))
            buf.write('Content-Type: %s\r\n' % contenttype)
            # buffer += 'Content-Length: %s\r\n' % file_size
            fd.seek(0)
            buf.write('\r\n' + fd.read() + '\r\n')
        buf.write('--' + boundary + '--\r\n\r\n')
        buf = buf.getvalue()
        return boundary, buf
    multipart_encode = Callable(multipart_encode)
 
    https_request = http_request
 
def main():
    import tempfile, sys
 
    validatorURL = "http://validator.w3.org/check"
    opener = build_opener(MultipartPostHandler)
 
    def validateFile(url):
        temp = tempfile.mkstemp(suffix=".html")
        os.write(temp[0], opener.open(url).read())
        params = { "ss" : "0",            # show source
                   "doctype" : "Inline",
                   "uploaded_file" : open(temp[1], "rb") }
        print(opener.open(validatorURL, params).read())
        os.remove(temp[1])
 
    if len(sys.argv[1:]) > 0:
        for arg in sys.argv[1:]:
            validateFile(arg)
    else:
        validateFile("http://www.google.com")
 
if __name__=="__main__":
    main()